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Does creatine increase strength? Many athletes believe that they experience strength improvements as a result of creatine supplementation. Long term creatine or creatine containing supplements have been reported to promote greater gains in strength, sprint performance and fat free body mass during training in comparison to paired controls. Consequently, creatine has become one of the most popular nutritional supplements marketed to athletes. (5) First, we will examine what creatine is, and how it is used in the body.
Creatine is an amino acid, like the building blocks that make up proteins. Creatine in the form of phosphocreatine (creatine phosphate) is an important store of energy in muscle cells. During intense exercise, phosphocreatine is broken down to creatine and phosphate, and the energy released is used to regenerate ATP (adenosine triphosphate), the primary source of cellular energy. It is believed that extra creatine in the muscle may increase the rate of regeneration of phosphocreatine. Creatine also helps dissipate the lactic acid that builds up in muscles during intense exercise. (4) This could mean that an athlete should experience less fatigue in training or in sports competitions.
Creatine is advertised as an ergogenic aid. Ergogenics are substances that may or are perceived to enhance performance through improved strength, speed, response time or endurance of an athlete. According to current theory, creatine supplementation increases the bioavailability of phosphocreatine (PCR) in skeletal muscle cells. This increase is thought to enhance muscle performance in two ways. First, more available PCR allows faster re-synthesis of ATP to provide energy for brief, high intensity exercise, like sprinting, jumping, or weight lifting. Second, PCR buffers the intracellular hydrogen ions associated with lactate production and muscle fatigue during exercise. Therefore, creatine supplementation may provide an ergogenic effect by increasing the force of muscular contraction. (1)
In studies conducted for supplementation strategies, the largest improvements in performance appear to be found in persons with the largest increases in muscle creatine concentration. This suggests that an ergogenic effect of creatine ingestion on metabolism and performance during exercise and recovery may critically depend on the extent of muscle creatine uptake during ingestion. It also points to the importance of maximizing tissue creatine uptake when attempting to increase exercise performance via creatine ingestion. (2)
Creatine has been used as a nutritional supplement for over ten years. Along with the ergogenic (strength) studies that have been conducted on the side effects of creatine supplementation, as well as the long-term creatine supplementation kidney functions. It is common to hear reports from athletes regarding muscle cramping or strains while supplementing with creatine. Diarrhea and gastrointestinal pain have also been reported. On average, supplementation includes 1-2 grams of creatine daily. It may be reasonable to assume that a loading dose of 20 grams daily for 5 days is excessive for some people’s digestive systems. There has also been concern that the water retention resulting from creatine supplementation can increase the risk of dehydration due to fluid shifts into the skeletal muscle cells. While this has not been proven, most manufacturers advise proper hydration while taking creatine to reduce this risk. Subjective reports and two published reports of kidney dysfunction in subjects taking creatine have raised concern about the effects of creatine supplementation on the kidneys. Short-term (5-day) creatine supplementation does not appear to impair kidney function in the healthy kidney function. However, supplementation greatly increases the urinary creatine excretion rate, as much as 90-fold during the loading phase and whether this has long-term adverse effects is unclear. Currently, creatine supplementation should not be used by people with pre-existing kidney disease or by those who have diabetes. (3)
The studies do indicate that you can get bigger stores of creatine and phosphate into muscles. It also shows that it enhances performance and generates more power output during intense exercise. Long-term creatine supplementation produces greater gains in strength and performance and may increase lean body mass. Depending on your athletic goals, you should research the benefits and possible side effects of creatine before starting a supplementation regimen.
References:
(1) Armsey Jr., M.D., Thomas D.; Green, M.D., Gary A.; (June 1997). Nutrition Supplements: Science vs. Hype. The Physician and Sportsmedicine – Vol. 25, No. 6.
(2) Casey, Anna; Greenhalf, Paul L. (Aug. 2000). Does Dietary Creatine Supplementation Play a Role in Skeletal Muscle Metabolism and Performance? American Journal of Clinical Nutrition – Vol. 72, No. 2, 6075 – 6175.
(3) Juhn, D.O., Mark S. (May 1999). Oral Creatine Supplementation. The Physician and Sportsmedicine. – Vol. 27, No. 5.
(4) Eichner, M.D., E. Randy. (April 1997). Ergogenic Aids: What Athletes Are Using and Why. The Physician and Sportsmedicine. – Vol. 25, No. 4.
(5) Kreider, Richard B. (April 1998). Creatine Supplementation: Analysis of Ergogenic Value, Medical Safety, and Concerns. Journal of Exercise Physiology. Vol. 1, No. 1.
Creatine is an amino acid, like the building blocks that make up proteins. Creatine in the form of phosphocreatine (creatine phosphate) is an important store of energy in muscle cells. During intense exercise, phosphocreatine is broken down to creatine and phosphate, and the energy released is used to regenerate ATP (adenosine triphosphate), the primary source of cellular energy. It is believed that extra creatine in the muscle may increase the rate of regeneration of phosphocreatine. Creatine also helps dissipate the lactic acid that builds up in muscles during intense exercise. (4) This could mean that an athlete should experience less fatigue in training or in sports competitions.
Creatine is advertised as an ergogenic aid. Ergogenics are substances that may or are perceived to enhance performance through improved strength, speed, response time or endurance of an athlete. According to current theory, creatine supplementation increases the bioavailability of phosphocreatine (PCR) in skeletal muscle cells. This increase is thought to enhance muscle performance in two ways. First, more available PCR allows faster re-synthesis of ATP to provide energy for brief, high intensity exercise, like sprinting, jumping, or weight lifting. Second, PCR buffers the intracellular hydrogen ions associated with lactate production and muscle fatigue during exercise. Therefore, creatine supplementation may provide an ergogenic effect by increasing the force of muscular contraction. (1)
In studies conducted for supplementation strategies, the largest improvements in performance appear to be found in persons with the largest increases in muscle creatine concentration. This suggests that an ergogenic effect of creatine ingestion on metabolism and performance during exercise and recovery may critically depend on the extent of muscle creatine uptake during ingestion. It also points to the importance of maximizing tissue creatine uptake when attempting to increase exercise performance via creatine ingestion. (2)
Creatine has been used as a nutritional supplement for over ten years. Along with the ergogenic (strength) studies that have been conducted on the side effects of creatine supplementation, as well as the long-term creatine supplementation kidney functions. It is common to hear reports from athletes regarding muscle cramping or strains while supplementing with creatine. Diarrhea and gastrointestinal pain have also been reported. On average, supplementation includes 1-2 grams of creatine daily. It may be reasonable to assume that a loading dose of 20 grams daily for 5 days is excessive for some people’s digestive systems. There has also been concern that the water retention resulting from creatine supplementation can increase the risk of dehydration due to fluid shifts into the skeletal muscle cells. While this has not been proven, most manufacturers advise proper hydration while taking creatine to reduce this risk. Subjective reports and two published reports of kidney dysfunction in subjects taking creatine have raised concern about the effects of creatine supplementation on the kidneys. Short-term (5-day) creatine supplementation does not appear to impair kidney function in the healthy kidney function. However, supplementation greatly increases the urinary creatine excretion rate, as much as 90-fold during the loading phase and whether this has long-term adverse effects is unclear. Currently, creatine supplementation should not be used by people with pre-existing kidney disease or by those who have diabetes. (3)
The studies do indicate that you can get bigger stores of creatine and phosphate into muscles. It also shows that it enhances performance and generates more power output during intense exercise. Long-term creatine supplementation produces greater gains in strength and performance and may increase lean body mass. Depending on your athletic goals, you should research the benefits and possible side effects of creatine before starting a supplementation regimen.
References:
(1) Armsey Jr., M.D., Thomas D.; Green, M.D., Gary A.; (June 1997). Nutrition Supplements: Science vs. Hype. The Physician and Sportsmedicine – Vol. 25, No. 6.
(2) Casey, Anna; Greenhalf, Paul L. (Aug. 2000). Does Dietary Creatine Supplementation Play a Role in Skeletal Muscle Metabolism and Performance? American Journal of Clinical Nutrition – Vol. 72, No. 2, 6075 – 6175.
(3) Juhn, D.O., Mark S. (May 1999). Oral Creatine Supplementation. The Physician and Sportsmedicine. – Vol. 27, No. 5.
(4) Eichner, M.D., E. Randy. (April 1997). Ergogenic Aids: What Athletes Are Using and Why. The Physician and Sportsmedicine. – Vol. 25, No. 4.
(5) Kreider, Richard B. (April 1998). Creatine Supplementation: Analysis of Ergogenic Value, Medical Safety, and Concerns. Journal of Exercise Physiology. Vol. 1, No. 1.
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